Electric bell.



No. 827,077. PATENTED JULY 31, 1906. E. J. BURKE.

, ELECTRIC BELL.

APPLICATION FILED MARJA, 1905.

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7 UN irijn STATES PATENT OFFICE.

TO JOHN Q. A. WHITTEMORE, OF BOSTON, MASSACHUSETTS.

ELECTRIC BELL.

Specification of Letters Patent.

Patented July 31, 1906.

. A lication filed March 14, 1905. Serial No. 250,000-

To all whom it may concern:

Be it known that I, EDWARD J. BURKE, a citizen of the United States, and a resident of Brooklyn, county of Kings, State of New York, have invented new and useful Improvements in Electric Bells, of which the following is a specification.

My invention relates to electric bells; and it has for its object to produce an electric bell which will ring in response to the changes in a vibratory current.

It has a further object to provide a bell wherein the adjustment of the clapper relative to the bell is entirely done away with and one wherein the construction permits of a compact arrangement of bell and means of operating the same.

This improvement more particularly relates to that class of bells which are made to ring by the operation of an electric current through an electromagnet. Heretofore it has been usual to employ a gong or bell arranged in such proximity to the actuating electromagnet that on the energization of the magnet by an electric current the pull of the magnet on its armature causes an attachment affixed to such armature to strike the bell or gong. In all such arrangements it is obvious that the bell or gong in its relation to the striking part of the armature must be so adjusted as to be within the range of its stroke. This adjustment is objectionable from the fact that it can rarely be made permanent because of the variations of current strength, which cause variations in the range of its armature-stroke. If the stroke of the arma ture be too forcible, the impact of the striking part will deaden the vibration of the bell and mar its clearness, and if too weak there will not be sufiicient force to cause any vibration. In my present improvement I affix directly to the armature a form of bell which will readily respond to every movement of such armature, whether to or from such magnet, so that any vibration whatever of such armature will cause sounding vibrations in the attached bell. Arranging these bells in this way has the advantage of ringing the bell each time the armature moves to and from the magnet, thus doubling the number of ringing vibrations possible by a single bell or gong rung in the ordinary way. It has the further advantage that the vibrations are not metal.

alarmingly sudden, but begin, increase, and diminish gradually. Another advantage of this arrangement is that it lessens the number of adjustments needed and insures the correct sounding of the bell no matter how vigorous or weak the armature may be operated by the magnet. It has the further advantage of greatly cheapening the construction of signal-bells and of diminishing the size of the frame of the bell, and consequently enabling the bells to be set up in much smaller space than is required for the present form of electric bells.

The invention consists in other features set forth in the following description, illustrated in the accompanying drawings, and claimed in the claim.

Referring to the drawings, Figure 1 illusrates a top view of my invention, and Fig. 2 illustrates a side view.

1 is the base of the electric bell.

11 and 12 are electromagnets mounted on the base and detachably secured thereto by the screws 17 and 18.

An armature 3 is mounted ona spring 4, which is attached to the base 1. An automatic circuit-breaker for producing vibrations in the electric current is supported on the base 1 in an insulator 20. The circuitbreaker consists of the post 19, having an adjusting-screw 5. One end of the spring 4 is located in proximity to one end of the screw 5 and makes contact therewith when the magnets are deenergized. Binding-posts 15 and 16 are supported in insulators 13 and 14,

located in the base 1.

A pin 8 is attached to the armature 3. The upper end of the pin 8 is provided with an enlargement 7, formed of stamped sheet A bell 6, having a clapper 21 located on the inside thereof, is attached to the spring 8 by means of a screw passing through the sheet-metal piece 7, located on the end of the in 8. p When the armature is drawn down by the operation of the magnets 11 and 12, the circuit through the magnets 1 1 and 12 is broken between the spring4and the contact 5. The armature then springs back until the spring 4 strikes the pin 5, when the circuit is again closed and the magnets 11 and 12 are again energized. The armature thus vibrates and causes the bell to vibrate. The inertia of the clapper located within the bell causes it to strike the sides of the bell as the bell moves to and from the magnets.

What I claim as new, and desire to secure by Letters Patent, is as follows:

In a bell the combination of an electromagnet, an armature supported so as to be operated by the said electromagnet, a springcontact mounted on the said armature and "forming an elastic support for the said armature, a stationary contact adapted to make contact with the said spring-contact, the said contacts adapted to make and break the circuit through the said electromagnet, a slender elastic arm connected at one end to the said armature, a substantially spherical bell connected to the other end of the said slender elastic arm, a free and unconnected metallic ball resting on the bottom of the interior of the said bell and adapted to at first roll on the said surface and later to strike from side to side on the lower part of the bell and to strike from side to side at the center of the bell as the Vibration of the armature increases in its rate and according to the intensity of the current passing through the electromagnet.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDWARD J. BURKEa Witnesses:

FAUST F. CRAMPTON, GEO. F. BENTLEY. 

